The PET sheet produced by the PET sheet production line has good self barrier performance to oxygen and water vapor, and is non-toxic and sanitary. It can be used for the packaging of food, medicine and medical equipment, and can be disinfected by y-ray. It has good adaptability to environmental protection and can be recycled economically and conveniently. Therefore, PET sheet produced by PET sheet production line is considered as an ideal packaging material to meet the requirements of environmental protection.